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Titan-Dunes-PIA09115.jpgTitanian Dunes54 visiteCaption NASA:"This radar image of Titan's well-known dunes is distinctive because it may show an age relationship between different classes of features on the surface of this frigid world.
Taken by Cassini's radar mapper on Jan. 13, 2007, during a flyby of Titan, three kinds of terrain can be seen. Throughout the image, the fine striping has been identified as dunes, possibly made from organic material and formed by wind activity. Dunes are a common landform on Titan.
The bright material at the lower right of the image is interpreted as being topographically higher than the dunes that go around it, and several circular features seen at the top center may be craters that are slowly being buried by the dunes. Since the dunes seem to lie over the craters, the dune activity probably occurred later in time.
This image was taken in synthetic aperture mode and has a resolution of approx. 350 mt (1150 feet).
North is toward the top left corner of the image, which is approx. 160 x 150 Km wide".MareKromium
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Titan-Dunes-PIA11802.jpgAt the Edge of Titan's Dunes54 visiteThis is a portion of a Cassini Radar Mapper image obtained by the Cassini Spacecraft on its Dec. 21, 2008, flyby of Saturn's moon Titan.
The area shown covers the southern boundary of an equatorial band where longitudinal dunes (dunes that form along the wind direction) are pervasive.
Here the dunes are apparently created by winds locally coming from the West and North-West, and generally blowing toward the East. The dunes are interspersed with radar-bright features that are inferred to rise above the surrounding terrain.
In the lower part of the image there are no dunes at all, and the texture is more typical of featureless plains observed in many other areas of Titan that lack dunes.
In this Transition Zone, the sand-sized particles that make up the dunes might not be so plentiful. In this case, insufficient sand to replenish the dunes makes them gradually disappear.
To compare the nature of these dunes to those seen at the Northern Boundary of the dune fields observed in radar images obtained during the T3 flyby on Feb. 15, 2005 see PIA07009.
The image is centered near 19,2° South Lat. and 257,4° West Long.
It covers an area of about 220 Km (approx. 137 miles) by about 170 Km (approx. 106 miles). North is approximately toward the top of the image, the radar illumination is from the right, and the Solar Incidence Angle is about 25° (meaning that the Sun was 65° above the Local Horizon).
The vertical stripe across the image at its center is an artifact in this preliminary version.MareKromium
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Titan-Dunes_and_Ridges-PIA03566.jpgPossible Tectonic fractures on Titan54 visiteOriginal caption:"This synthetic aperture radar image of Titan was taken on Oct. 28, 2005, as the Cassini spacecraft flew by at a distance of 1.350 Km (about 840 miles). This was the first pass dedicated to radar and it was the fourth time Cassini's radar honed in on the smoggy moon.
The bright, curving features are high-standing ridges, poking up above the plains of Titan. Some of the ridges extend for over 100 Km (roughly 60 miles). They are likely to be tectonic in origin, formed by deformation of Titan's icy crust. The low-lying terrain between the ridges is covered in dark streaks, which could be dunes formed by wind. The streaks, spaced 1 to 2 Km apart (0,6 to 1 mile), curve between patches of the bright terrain, which probably act as topographic barriers.
This image is 400 Km (about 250 miles) across and 275 Km-wide (about 170 miles). It is located 8° South Latitude and 215° West Longitude".
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Titan-EB-MV.jpg"Methane View" of Titan (credits: Elisabetta Bonora)55 visitenessun commentoMareKromium
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Titan-EB.gifTitan (highly overexposed) with Startrails and a really bizarre "Light-Shadows' Effect" (GIF-Movie; credits: Elisabetta Bonora - Lunexit Team)55 visitenessun commentoMareKromium
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Titan-EB.jpgCrescent Titan: IR View, from N00152286 (Natural Colors; Special Processing by Elisabetta Bonora - Lunexit Team)55 visitenessun commentoMareKromium
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Titan-Fensal_and_Aztlan-PIA07732-PCF-LXTT-IPF-0.jpgFensal and Aztlan (CTX Image-Mosaic - Absolute Natural Colors; credits for the additional process. and color.: Dr Paolo C. Fienga/Lunar Explorer Italia/Italian Planetary Foundation)59 visiteDuring its September 7, 2005, Fly-By of the Saturnian moon Titan, the NASA - Cassini Spacecraft acquired a series of images of a Territory located on the moon's Saturn-facing Hemisphere that were afterwards assembled so to create this small mosaic: once known only as "The H" (because this whole Region looks something like the letter "H", when oriented on its side), the Surface Features visible here now possess provisional names that were assigned to them by the International Astronomical Union (or "IAU", for short).
The Northern Branch of "The H" is now called "Fensal," while the Southern Branch is known as "Aztlan."
Fensal is littered with small "Island-like Landforms" ranging in size from about 5 to 40 Km (such as from approx. 3,1 to a little less than 25 miles) across. These Landforms currently are thought to be Water-Ice Upland Areas (---> kind of small Hills), surrounded by shallower Terrain that is filled-in with dark Particulate Material probably precipitated from the Lower Atmosphere of Titan. In Western Fensal, a few larger Islands can also be seen, like Bazaruto Facula (visible to the right here and containing what seems to be an Impact Crater or, maybe, a Volcanic Edifice). When viewed in images of Shangri-La (another Titanian Region located on the opposite side of Titan as to Fensal and Aztlan), the Island-like Landforms of this size tend to occur in "clusters" (---> groups) with an apparent so-called "Preferred Orientation" (perhaps due to the action of the Dominant Winds blowing over those Territories). The small Islands found in Fensal, instead, appear much more scattered (and most of them appear roughly circular), although a few Islands do have (show) an East-West orientation to their long axis.
Aztlan, on the other hand, appears comparatively devoid of small Island-like Landforms, with only three large Islands located in its Western Reaches, plus only a few smaller Islands. The largest one of these Landforms is called "Sotra Facula" (visible just right of center in the bottom left portion of the mosaic), and measures approx. 240 by 120 Km (such as about 149 to 74,52 miles) across.
The mosaic is centered at 7° North Latitude and 21° West Longitude on Titan and the frames composing it were taken by the NASA - Cassini Spacecraft Narrow-Angle Camera using a filter sensitive to Wavelengths of Near-InfrarRed Light centered at 938 nanometers. They were acquired at distances ranging from approximately 200.600 to 191.800 Km (such as from about 124.572 to 119.108 miles) from Titan. The Mean Resolution in the images forming the mosaic is about 2 Km (such as 1,242 miles) per pixel.
This picture (which is an Original NASA - Cassini Spacecraft b/w image-mosaic published on the NASA - Planetary Photojournal and identified by the n. PIA 07732) has been additionally processed, magnified, contrast enhanced and then colorized, according to an educated guess carried out by Dr Paolo C. Fienga (LXTT-IPF), in Absolute Natural Colors (such as the colors that a human eye would actually perceive if someone were onboard the NASA - Cassini Spacecraft and then looked outside, towards the Saturnian moon Titan), by using an original technique created - and, in time, dramatically improved - by the Lunar Explorer Italia Team. Different colors, as well as different shades of the same color, mean, among others, the existence of different Elements present in the Atmosphere and on the Surface of Titan, each having a different Albedo (---> Reflectivity) and Chemical Composition.
Note: it is possible (but we, as IPF, have no way to be one-hundred-percent sure of such a circumstance), that the actual luminosity of the Clouds and Hazes (as well as the luminosity of the Surface of Titan itself), as seen in this mosaic, would appear, to an average human eye, way lower than it has been shown (or, better yet: interpreted) here.MareKromium
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Titan-Fensal_and_Aztlan-PIA07732-PCF-LXTT-IPF-1.jpgFensal (EDM - Absolute Natural Colors; credits for the additional process. and color.: Dr Paolo C. Fienga/Lunar Explorer Italia/Italian Planetary Foundation)55 visiteDuring its September 7, 2005, Fly-By of the Saturnian moon Titan, the NASA - Cassini Spacecraft acquired a series of images of a Territory located on the moon's Saturn-facing Hemisphere that were afterwards assembled so to create this small mosaic: once known only as "The H" (because this whole Region looks something like the letter "H", when oriented on its side), the Surface Features visible here now possess provisional names that were assigned to them by the International Astronomical Union (or "IAU", for short).
The Northern Branch of "The H" (shown in this EDM) is now called "Fensal," while the Southern Branch is known as "Aztlan."
Fensal is littered with small "Island-like Landforms" ranging in size from about 5 to 40 Km (such as from approx. 3,1 to a little less than 25 miles) across. These Landforms currently are thought to be Water-Ice Upland Areas (---> kind of small Hills), surrounded by shallower Terrain that is filled-in with dark Particulate Material probably precipitated from the Lower Atmosphere of Titan. In Western Fensal, a few larger Islands can also be seen, like Bazaruto Facula (visible in the upper right corner here and containing what seems to be an Impact Crater or, maybe, a Volcainc Edifice). When viewed in images of Shangri-La (another Titanian Region located on the opposite side of Titan as to Fensal and Aztlan), the Island-like Landforms of this size tend to occur in "clusters" (---> groups) with an apparent so-called "Preferred Orientation" (perhaps due to the action of the Dominant Winds blowing over those Territories). The small Islands found in Fensal, instead, appear much more scattered (and most of them appear roughly circular), although a few Islands do have (show) an East-West orientation to their long axis.
The mosaic is centered at 7° North Latitude and 21° West Longitude on Titan and the frames composing it were taken by the NASA - Cassini Spacecraft Narrow-Angle Camera using a filter sensitive to Wavelengths of Near-InfrarRed Light centered at 938 nanometers. They were acquired at distances ranging from approximately 200.600 to 191.800 Km (such as from about 124.572 to 119.108 miles) from Titan. The Mean Resolution in the images forming the mosaic is about 2 Km (such as 1,242 miles) per pixel.
This picture (which has been cropped from an Original NASA - Cassini Spacecraft b/w image-mosaic published on the NASA - Planetary Photojournal and identified by the n. PIA 07732) has been additionally processed, magnified, contrast enhanced and then colorized, according to an educated guess carried out by Dr Paolo C. Fienga (LXTT-IPF), in Absolute Natural Colors (such as the colors that a human eye would actually perceive if someone were onboard the NASA - Cassini Spacecraft and then looked outside, towards the Saturnian moon Titan), by using an original technique created - and, in time, dramatically improved - by the Lunar Explorer Italia Team. Different colors, as well as different shades of the same color, mean, among others, the existence of different Elements present in the Atmosphere and on the Surface of Titan, each having a different Albedo (---> Reflectivity) and Chemical Composition.
Note: it is possible (but we, as IPF, have no way to be one-hundred-percent sure of such a circumstance), that the actual luminosity of the Clouds and Hazes (as well as the luminosity of the Surface of Titan itself), as seen in this mosaic, would appear, to an average human eye, way lower than it has been shown (or, better yet: interpreted) here.MareKromium
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Titan-Full_Disk-PIA02145-1.jpgTitan: Visual + IMS (1)54 visiteThe three mosaics shown here were composed with data from Cassini's visual and infrared mapping spectrometer taken during the last 3 Titan flybys, on Oct. 28, 2005 (1), Dec. 26, 2005 (2), and Jan. 15, 2006 (3).
These false-color images were constructed from images taken at the following wavelengths: 1,6 microns (blue), 2,01 (green), and 5 microns (red).
The viewing geometry of the December flyby is roughly on Titan's opposite Hemisphere from the flybys in October and January.
There are several important features to note in the images. The first is that the South Polar cloud system was very bright during the December flyby, while during the October and January flybys, it is barely visible, indicating that the atmosphere over Titan's South Pole is very dynamic.
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Titan-Full_Disk-PIA02145-2.jpgTitan: Visual + IMS (2)54 visiteIn the December (2) mosaic, a North Polar hood that is bright at 5 microns is visible. Its composition is unknown.
The North Polar hood is barely seen in the October (1) and January (3) data.
Visible in the October and December images just South of the Equator is Tui Reggio, a Region nicknamed the "chevron". This Region is very bright at 5 microns and is among the brightest features on Titan at that wavelength.
Tui Reggio is thought to be a surface deposit, probably of volcanic origin, and may be water and/or carbon dioxide frozen from the vapor.
The December flyby data show that the western margins of Tui Reggio have a complex flow-like character consistent with eruptive phenomena.
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Titan-Full_Disk-PIA02145-3.jpgTitan: Visual + IMS (3)54 visitenessun commento
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Titan-Full_Disk-PIA06141_modest.jpgTitan (full disk, no haze) from 300.000 up to 650.000 Km58 visiteThe images that comprise the mosaic have been processed to reduce the effects of the atmosphere and to sharpen surface features. The mosaic has been trimmed to show only the illuminated surface and not the atmosphere above the edge of the moon. Pixel scales of the composite images vary from 2 to 4 Km per pixel. Surface features are best seen near the center of the disc, where the spacecraft is looking directly downwards; the contrast becomes progressively lower and surface features become fuzzier toward the outside, where the spacecraft is peering through haze, which washes out surface features. The brighter region on the right side and equatorial region is named Xanadu. Scientists are debating what processes may have created the bizarre surface brightness patterns seen here. The images hint at a young surface with no obvious craters. The exact nature of that activity, whether tectonic, wind-blown, fluvial, marine or volcanic is still unknown.
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